The University of Hong Kong
Platform Technology Funding 
High-Performance Integrated Robotic Systems for Intra-operative MRI-guided Interventions
Gallery Photo.png
 
Research Topics

Objective of the project:

The overall goal of this project is to develop high-performance integrated robotic systems for intra-operative multiple MRI-guided interventions, including 1) prostate brachytherapy, 2) bladder photothermal therapy, 3) functional and stereotactic neurosurgery, and 4) transoral laser microsurgery. This project will integrate advanced technologies from different areas of medical robotics, namely fast intra-op MRI, high-performance MR-safe/conditional actuators and real-time MR-tracking units, with the aim at becoming benchmark systems to engage multidisciplinary collaborations with surgery and radiology. Potential downstream application will be foreseen for further R&D with the currently strong and sustainable support from our industrial partners.

 

Significance of the project:

Advanced surgical robotics has attracted significant research interest in supporting magnetic resonant imaging (MRI)-based visual guidance for effective navigation of surgical instruments. MRI offers excellent image contrast for soft tissue details and differentiations, allowing clinicians to identify tumors margins and critical neurovascular and muscular structures. By acquiring intra-operative (intra-op) MR images rapidly, 3-D critical regions showing the physiological changes of tissue can be visualized. In minimally invasive interventions, such in situ guidance providing access routes to the target anatomy, rendered based on imaging data, can enable a distinct awareness of the configuration of robotic instrument relative to the anatomy of surgical interest.

 

Integration of multidisciplinary technologies for intra-op MRI-guided interventions

In this project, fast image processing techniques, novel MR-safe/conditional robotic components, as well as real-time MR-tracking are proposed to fulfil the unmet technological requirements for providing safe, precise and effective control of instruments in MRI-guided minimally invasive surgeries. Advanced computing technique is presented to enable instant, frequent update of anatomical roadmap using reliable image registration based on intra-op imaging data, since its slow computational process is still the major bottleneck in real implementation on many image-guided interventions. The proposed MR-safe/conditional robotic components could be even operated in MRI environment that imposes significant difficulties on conventional robot operations due to the tremendously strong magnetic field generated by the scanner. Soft continuum robotic manipulator made of biocompatible elastomer is also presented to facilitate luminal exploration while still guaranteeing the diagnostic and therapeutic capabilities. This soft robot would act as the next-generation of endoscope in the new standards of less pain, low cost, single use and zero chance of cross-infection. In addition, the proposed miniaturized tracking units can be integrated with minimal invasive surgical devices (e.g. catheter), providing accurate real-time positional tracking. Not only can they be visualized in the MR images intra-operatively, they can also close the control loop of the robotic interventions.

Integrated robotic platform for various MRI-guided minimal invasive interventions

The proposed MR-conditional robotic platform will be the first of its kind which integrates advanced multidisciplinary technologies of accelerated intra-op MR image registration, enhanced control of flexible instrument (e.g. cystoscope), real-time MR-tracking units and high-performance MR-safe actuation. Successful completion of the proposed work will facilitate comprehensive pre-clinical validation in human trials. A new line of study will be developed, attracting clinicians to push the envelope of robot-assisted interventions, in particular for the procedures stated in the following section.

 

Main projects incurred:

 

Intra-op MRI-guided prostate brachytherapy: Prostate cancer is a common cancer. Let alone in the US, above 450,000 new cases are expected to be diagnosed, more than double by the year 2015. The use of intra-op MR images (e.g. T2-weighted or diffusion tensor) in guiding the biopsy or drug delivery to prostate gland becomes the trend led by minimally invasive approaches. It will eliminate the need for any image fusion with transrectal ultrasound (TRUS), which is commonly used as the intra-op imaging, causing much spatial error in surgical planning. Our proposed MR-conditional robotic platform could i) resolve the surgical complications of radical prostatectomy with the presence of deep venous thrombosis, pulmonary embolism, urinary incontinence, and impotence; ii) reduce the failure rate of biopsy or needle insertion, since every needle placed can be imaged and assessed in 3D, and then repositioned before further insertion; iii) improve the accuracy of brachytherapy seeds placement/distribution (<1mm RMS).

Intra-op MRI-guided bladder photothermal therapy:  Non-muscle-invasive bladder cancer (NMIBC) accounts for 80% of all diagnosed cases of bladder cancer, and has a recurrence rate of up to 61% at one year, and 78% at five years, despite bladder cancer ranked 8th by the mortality rate worldwide. In cases where the cancer progresses to muscle-invasive bladder cancer, complete removal of the bladder, called radical cystectomy, is usually performed. The requirement of urine diversion following this procedure is associated with the worst health-related quality of life for patients. This fact creates great demand for a more complete and reliable first-line treatment to NMIBC. The successful integration of MRI-guided, robot-assisted cystoscopic techniques with gold-nanoparticle-based photothermal therapy (PTT) would present a timely improvement over current first-line treatments for bladder cancer, addressing several key points: i) improved tumor localization by the use of MR-contrasting agents coated on tumor-accumulated GNPs, instead of relying on visual detection via cystoscopy; ii) reducing the recurrence rate of NMIBC by providing complete tumor ablation, thereby lowering the dependence on frequent post-operative surveillance; iii) minimizing the possibility of patient progression to the advanced stages of bladder cancer, which require curative procedures that significantly diminish patient quality-of-life.

 

Intra-op MRI-guided functional and stereotactic neurosurgery: Deep brain stimulation (DBS) is one of the common neurosurgical procedures for alleviate symptoms associated with essential tremor, Parkinson’s disease (PD) and dystonia, in which a coiled wire is placed at different regions of the brain, such as ventrointermediate nucleus (VIM) or subthalamic nucleus (STN), under stereotactic guidance to interfere with neural activity at the region. Under the MRI image, the STN and other critical brain structures can be clearly revealed. It is anticipated that our MR-conditional robotic system could: i) enhance the accuracy (±1mm) of electrode placement by coping with brain shifts using updated brain images and MR-tracked instruments; ii) decrease the risks of damaging the critical brain structure; iii) avoid the complications of local anaesthesia, thus adding confidence by having the post-procedural evaluations of surgical outcome based on images, instead of verbal/physical interaction with the awake patient during the procedure; iv) save the operation time from the repeated microelectrode recording (MER) as well as the image alignment with head frame. The procedural time will be reduced from approximately >330 to 180 minutes. The overall healthcare expenditure could be significantly reduced, also compensating the cost of using MRI.

Objective of the project:

The overall goal of this project is to develop high-performance integrated robotic systems for intra-operative multiple MRI-guided interventions, including 1) prostate brachytherapy, 2) bladder photothermal therapy, 3) functional and stereotactic neurosurgery, and 4) transoral laser microsurgery. This project will integrate advanced technologies from different areas of medical robotics, namely fast intra-op MRI, high-performance MR-safe/conditional actuators and real-time MR-tracking units, with the aim at becoming benchmark systems to engage multidisciplinary collaborations with surgery and radiology. Potential downstream application will be foreseen for further R&D with the currently strong and sustainable support from our industrial partners.

 

Significance of the project:

Advanced surgical robotics has attracted significant research interest in supporting magnetic resonant imaging (MRI)-based visual guidance for effective navigation of surgical instruments. MRI offers excellent image contrast for soft tissue details and differentiations, allowing clinicians to identify tumors margins and critical neurovascular and muscular structures. By acquiring intra-operative (intra-op) MR images rapidly, 3-D critical regions showing the physiological changes of tissue can be visualized. In minimally invasive interventions, such in situ guidance providing access routes to the target anatomy, rendered based on imaging data, can enable a distinct awareness of the configuration of robotic instrument relative to the anatomy of surgical interest.

 

Integration of multidisciplinary technologies for intra-op MRI-guided interventions

In this project, fast image processing techniques, novel MR-safe/conditional robotic components, as well as real-time MR-tracking are proposed to fulfil the unmet technological requirements for providing safe, precise and effective control of instruments in MRI-guided minimally invasive surgeries. Advanced computing technique is presented to enable instant, frequent update of anatomical roadmap using reliable image registration based on intra-op imaging data, since its slow computational process is still the major bottleneck in real implementation on many image-guided interventions. The proposed MR-safe/conditional robotic components could be even operated in MRI environment that imposes significant difficulties on conventional robot operations due to the tremendously strong magnetic field generated by the scanner. Soft continuum robotic manipulator made of biocompatible elastomer is also presented to facilitate luminal exploration while still guaranteeing the diagnostic and therapeutic capabilities. This soft robot would act as the next-generation of endoscope in the new standards of less pain, low cost, single use and zero chance of cross-infection. In addition, the proposed miniaturized tracking units can be integrated with minimal invasive surgical devices (e.g. catheter), providing accurate real-time positional tracking. Not only can they be visualized in the MR images intra-operatively, they can also close the control loop of the robotic interventions.

Integrated robotic platform for various MRI-guided minimal invasive interventions

The proposed MR-conditional robotic platform will be the first of its kind which integrates advanced multidisciplinary technologies of accelerated intra-op MR image registration, enhanced control of flexible instrument (e.g. cystoscope), real-time MR-tracking units and high-performance MR-safe actuation. Successful completion of the proposed work will facilitate comprehensive pre-clinical validation in human trials. A new line of study will be developed, attracting clinicians to push the envelope of robot-assisted interventions, in particular for the procedures stated in the following section.

 

Main projects incurred:

 

Intra-op MRI-guided prostate brachytherapy: Prostate cancer is a common cancer. Let alone in the US, above 450,000 new cases are expected to be diagnosed, more than double by the year 2015. The use of intra-op MR images (e.g. T2-weighted or diffusion tensor) in guiding the biopsy or drug delivery to prostate gland becomes the trend led by minimally invasive approaches. It will eliminate the need for any image fusion with transrectal ultrasound (TRUS), which is commonly used as the intra-op imaging, causing much spatial error in surgical planning. Our proposed MR-conditional robotic platform could i) resolve the surgical complications of radical prostatectomy with the presence of deep venous thrombosis, pulmonary embolism, urinary incontinence, and impotence; ii) reduce the failure rate of biopsy or needle insertion, since every needle placed can be imaged and assessed in 3D, and then repositioned before further insertion; iii) improve the accuracy of brachytherapy seeds placement/distribution (<1mm RMS).

Intra-op MRI-guided bladder photothermal therapy:  Non-muscle-invasive bladder cancer (NMIBC) accounts for 80% of all diagnosed cases of bladder cancer, and has a recurrence rate of up to 61% at one year, and 78% at five years, despite bladder cancer ranked 8th by the mortality rate worldwide. In cases where the cancer progresses to muscle-invasive bladder cancer, complete removal of the bladder, called radical cystectomy, is usually performed. The requirement of urine diversion following this procedure is associated with the worst health-related quality of life for patients. This fact creates great demand for a more complete and reliable first-line treatment to NMIBC. The successful integration of MRI-guided, robot-assisted cystoscopic techniques with gold-nanoparticle-based photothermal therapy (PTT) would present a timely improvement over current first-line treatments for bladder cancer, addressing several key points: i) improved tumor localization by the use of MR-contrasting agents coated on tumor-accumulated GNPs, instead of relying on visual detection via cystoscopy; ii) reducing the recurrence rate of NMIBC by providing complete tumor ablation, thereby lowering the dependence on frequent post-operative surveillance; iii) minimizing the possibility of patient progression to the advanced stages of bladder cancer, which require curative procedures that significantly diminish patient quality-of-life.

 

Intra-op MRI-guided functional and stereotactic neurosurgery: Deep brain stimulation (DBS) is one of the common neurosurgical procedures for alleviate symptoms associated with essential tremor, Parkinson’s disease (PD) and dystonia, in which a coiled wire is placed at different regions of the brain, such as ventrointermediate nucleus (VIM) or subthalamic nucleus (STN), under stereotactic guidance to interfere with neural activity at the region. Under the MRI image, the STN and other critical brain structures can be clearly revealed. It is anticipated that our MR-conditional robotic system could: i) enhance the accuracy (±1mm) of electrode placement by coping with brain shifts using updated brain images and MR-tracked instruments; ii) decrease the risks of damaging the critical brain structure; iii) avoid the complications of local anaesthesia, thus adding confidence by having the post-procedural evaluations of surgical outcome based on images, instead of verbal/physical interaction with the awake patient during the procedure; iv) save the operation time from the repeated microelectrode recording (MER) as well as the image alignment with head frame. The procedural time will be reduced from approximately >330 to 180 minutes. The overall healthcare expenditure could be significantly reduced, also compensating the cost of using MRI.

 
Dr Kwok photo.jpg
Dr. Ka-Wai Kwok

Associate Professor, Department of Mechanical Engineering

B.Eng, MPhil (CUHK), DIC, PhD (Imp Lond)
Research Interest: 

Surgical robotics, Intra-operative medical imaging processing, Human-robot control interface

Co-Investigator
Principal Investigator

Dr. Vince Vardhanabhuti

Clinical Assistant Professor, Department of Diagnostic Radiology

​MBBS BSc (Lond, UK), FRCR (UK), PhD(UK)
Research Interests: Radiation Protection; Low Dose Computed Tomography; Liver Imaging; Prostate Cancer; Artificial Intelligence

Dr. Charles Hing-Chiu Chang

Research Assistant Professor, Department of Diagnostic Radiology

B.S., M.S., PhD (NTU)
Research Interests: Pulse sequence development of fast magnetic resonance imaging technique for diffusion weighted imaging / functional MRI; Artifact removal of echo-planar imaging (EPI); Fat quantification using MRI
 

Recent Results

Intra-op Image-guided Robotics

High-performance Continuous Hydraulic Motor for MR Safe Robotic Teleoperation

[Video: High-performance Continuous Hydraulic Motor for MR Safe Robotic Teleoperation]

Magnetic resonance imaging (MRI)-guided intervention has drawn increasing attention over the last decade. It is accredited to the capability of monitoring any physiological change of soft tissue with the high-contrast MR images. This also gives rise to the demand for precise tele-manipulation of interventional instruments. However, there is still lack of choices of MR safe actuators that provide high-fidelity robot manipulation. In this project, we present a three-cylinder hydraulic motor using rolling-diaphragm-sealed cylinders, which can provide continuous bidirectional rotation with unlimited range. Both kinematics and dynamics models of the presented motor were studied, which facilitate its overall design optimization and position/torque control. Motor performance, such as step response, frequency response, and accuracy, were experimentally evaluated. We also integrate the motor into our catheter robot prototype designed for intra-operative MRI-guided cardiac electrophysiology (EP), which can provide full-degree-of-freedom and precise manipulation of a standard EP catheter.

MRI-guided Robot for Bilateral Stereotactic Neurosurgery

[Video: MRI-guided Robot for Bilateral Stereotactic Neurosurgery]

Stereotactic neurosurgery is a treatment to a variety of movement and neuropsychiatric disorders, such as Parkinson’s disease (PD), essential tremor and major depression. The operation still remains challenging due to its complicated workflow and high demand for surgical accuracy, which can be further complicated by deformation of intracranial contents, namely “brain shift”. These complications create an increasing need for intra-operative MRI-guided stereotaxy. Unlike fluoroscopy/CT, MRI can directly visualize the critical brain structures and targets of interest (e.g., the subthalamic nucleus (STN)). Currently, there are very limited choices of MR safe stereotactic systems. They generally require intensive manual adjustment of the stereotactic frame, and the patient to be transferred in-and-out of the scanner bore. This inevitably disrupts the normal surgical workflow. To this end, we have developed an intra-operative MRI-guided robot for bilateral stereotactic procedures. Its compact design enables robot’s operation within the constrained space of standard imaging head coil. MR-safe and high-performance hydraulic transmissions are incorporated, and wireless MR-based tracking coil units allow real-time positional feedback directly in MR image coordinates.

MRI-guided Robot for Intra-operative Cardiac Catheterization

[Video: MRI-guided Robot for Intra-operative Cardiac Catheterization]

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This robotic catheter platform intends to provide safe and effective electrophysiology (EP) intervention under the guidance of magnetic resonance imaging (MRI). In cardiac EP intervention, a long catheter (>1m) is delivered to the heart chamber where radiofrequency ablation (RFA) is performed to isolate the abnormal electrophysiological signals. The safety and effectiveness of EP intervention can be enhanced by providing high quality intra-operative MR images and MR-conditional robotic platform for effective catheterization. Currently, no existing commercial nor research prototype for robotic catheterization is MR-conditional. We develop the MR-conditional catheter robotic system for effective catheter manipulation that makes use of MR-safe/conditional actuation, intra-operative MRI techniques, real-time visual feedback and an advanced kinematics control method.

 
Selected Publications

selected publications 

1

Z. Guo, M.C.W. Leong, H. Su, K.W. Kwok, D.T.M. Chan, W.S. Poon, “Prospective Techniques for Magnetic Resonance
Imaging–Guided Robot-Assisted Stereotactic Neurosurgery,”
Handbook of Robotic and Image-Guided Surgery, pp. 585-598,2020.

selected publications 

2

C. L. Cheung, J. D. Ho, V. Vardhanabhuti, H. Chang and K. Kwok, "Design and Fabrication of Wireless Multilayer Tracking Marker for Intraoperative MRI-Guided Interventions," in IEEE/ASME Transactions on Mechatronics, vol. 25, no. 2, pp. 1016-1025, April 2020

selected publications 

3

Z. He, Z. Dong, G. Fang, J.D.L. Ho, C.L. Cheung, H.C. Chang, C.N. Chong, Y.K. Chan, T.M. Chan, K.W. Kwok, “Design of a Percutaneous MRI-guided Needle Robot with Soft Fluid-driven Actuator,” IEEE Robotics and Automation Letters vol. 5, no. 2, pp. 2100-2107 

selected publications 

4

X. Wang, G. Fang, K. Wang, X. Xie, K.H. Lee, J.D.L. Ho, W.L. Tang, J. Lam, K.W. Kwok, “Eye-in-hand Visual Servoing Enhanced with Sparse Strain Measurement for Soft Continuum Robots,” IEEE Robotics and Automation Letters, vol. 5, no. 2, pp. 2161-2168, April 2020 

selected publications 

5

X. Xie, J. Lam, K.W. Kwok, “A novel scheme of non-fragile controller design for periodic piecewise LTV systems,” IEEE Transactions on Industrial Electronics, 2020.  

selected publications 

6

P. Li, J. Lam, R. Lu, K.W. Kwok, “Stability and L2 Synthesis of a Class of Periodic Piecewise Time-Varying Systems,” IEEE Transactions on Automatic Control, 64(8):3378-3384, 2019. 

selected publications 

7

Y. Chen, C. Zhao, J. Lam, Y. Cui, K.W. Kwok, “Stability and l1-Gain Analysis for Positive 2-D Markov Jump Systems,” International Journal of Systems Science, 50(11):2077-2087, 2019.

selected publications 

8

H.C. Fu, J.D.L. Ho, K.H. Lee, Y.C. Hu, K.W. Au, K.J. Cho, K.Y. Sze, K.W. Kwok, “Interfacing soft and hard: a spring reinforced actuator,” Soft Robotics, 2019. 

selected publications 

9

W. Jiang, Z. Liu, K.H. Lee, S. Chen, Y.L. Ng, Q. Dou, H.C. Chang, K.W. Kwok, “Respiratory Motion Correction in Abdominal MRI using a Densely Connected U-Net with GAN-guided Training,” arXiv preprint, arXiv: 1906.09745, 2019.

selected publications 

10

J. Li, T. Kong, J. Yu, K.H. Lee, Y.H. Tang, K.W. Kwok, J.T. Kim, H.C. Shum, “Electrocoiling-guided Printing of Multiscale Architectures at Single-wavelength Resolution,” Lab on a Chip , 19(11):1953-1960, 2019.

selected publications 

11

Y. Chen, J. Lam, Y. Cui, J. Shen, K.W. Kwok, “Reachable Set Estimation and Synthesis for Periodic Positive Systems,” IEEE Transactions on Cybernetics, pp. 1-22, 2019. (Early Access)

selected publications 

12

Y. Fan, F. Yang, G.S.H. Cheung, A.K.Y. Chan, D.D. Wang, Y.Y. Lam, M.C.K. Chow, M.C.W. Leong, K.K.H. Kam, K.C.Y. So, G. Tse, E. Fung, Z. Qiao, B. He, K.W. Kwok, A.P.W. Lee, “Device Sizing Guided by Echocardiography-Based Three-Dimensional Printing is Associated with Superior Outcome after Percutaneous Left Atrial Appendage Occlusion,” Journal of the American Society of Echocardiography, 32(6):708-719, 2019.

selected publications 

13

Z. Tang, Y.T. Fan, Y. Wang, C.N. Jin, K.W. Kwok, A.P.W. Lee, “Mitral Annular and Left Ventricular Dynamics in Atrial Functional Mitral Regurgitation: A Three-Dimensional and Speckle-Tracking Echocardiographic Study,” Journal of the American Society of Echocardiography, 32(4):503-513, 2019.

selected publications 

14

Z. Dong, Z. Guo, K.H. Lee, G. Fang, W.L. Tang, H.C. Chang, D.T.M. Chan and K.W. Kwok, “High-performance Continuous Hydraulic Motor for MR Safe Robotic Teleoperation,” IEEE Robotics and Automation Letters, 4(2):1964-1971, 2019.

selected publications 

15

T.L.T. Lun, K. Wang, J.D.L. Ho, K.H. Lee, K.Y. Sze, K.W. Kwok, “Real-time Surface Shape Sensing for Soft and Flexible Structures using Fiber Bragg Gratings,” IEEE Robotics and Automation Letters, 4(2):1454-1461, 2019.

selected publications 

16

G. Fang, X. Wang, K. Wang, K.H. Lee, J.D.L. Ho, H.C. Fu, D.K.C. Fu, K.W. Kwok, “Vision-based Online Learning Kinematic Control for Soft Robots using Local Gaussian Process Regression,” IEEE Robotics and Automation Letters, 4(2):1194-1201, 2019.

selected publications 

17

M. Liu, J. Lam, B. Zhu, K.W. Kwok, “On Positive Realness, Negative Imaginariness, and H∞ Control of State-space Symmetric Systems,” Automatica, 101:190-196, 2019.

selected publications 

18

Z. Li, G. Fang, J.D.L. Ho, C.I. Lam, Y.W. Yim, J.Y.K. Chan, K.W. Kwok, “Augmented Reality-Guided Visual Servoing for Flexible Endoscope Control,” IEEE International Conference on Robotics and Automation (ICRA) Workshop – Open Challenges and State-of-the-Art in Control System Design and Technology Development for Surgical Robotic Systems, 2019. [Best Poster Paper Award (2nd place)]

selected publications 

19

Z. Liu, W. Jiang, K.H. Lee, Y.L. Lo, Y.L. NG, Q. Dou, V. Vardhanabhuti, K.W. Kwok, “A Two-Stage Approach for Automated Prostate Lesion Detection and Classification with Mask R-CNN and Weakly Supervised Deep Neural Network,” Medical Image Computing and Computer-Assisted Intervention (MICCAI) Workshop – Artificial Intelligence in Radiation Therapy. Springer, Cham, pp. 43-51, 2019.

selected publications 

20

Z. Dong, X. Wang, Z. He, J.D.L. Ho, W.L. Tang, Y. Tao, A.P.W. Lee, K.W. Kwok, “Experimental Validation of Autonomous Motion Control with Standard Cardiac Electrophysiology Catheter,” IEEE International Conference on Robotics and Automation (ICRA) Workshop – Open Challenges and State-of-the-Art in Control System Design and Technology Development for Surgical Robotic Systems, 2019.
[Best Poster Paper Award (2nd place)]

Patents Filed

patents

1

“Fluid-driven Robotic Needle Positioner for Image-Guided Percutaneous Interventions”
US Provisional Pat.: US 63/053,798 [Filed on 24 Jul 2020]

patents

2

“Visual Servoing of An MR-safe Soft Manipulator for Transoral Laser Microsurgeries”

US Provisional Pat: US 63/021,692 [Filed on 8 May 2020]

patents

3

“Enhanced Magnetic Resonance Imaging Guidance for Robotic Transoral Surgery”

US Provisional Pat.: US 62/898,072 [Filed on 10 Sep 2019]

patents

4

“Real-time Surface Shape Sensing for Flexible Structures Using Fiber Bragg Gratings”,

US Pat.: US 16/449,063 [Filed on 21 Jun 2019]; CN Pat.: CN 201910552110.1 [Filed on 24 Jun 2019]